1. Field of the Invention
The present invention relates generally to paint systems for vehicles and, more specifically, to an integrated paint quality control system for feedback control of paint process for painting bodies of vehicles.
2. Description of the Related Art
The application of paint to a body of a vehicle is a sensitive process. The quality, durability and color matching of the paint are critical in producing a high quality product, and therefore require significant quality control efforts. A paint booth is used to apply the paint to the vehicle bodies. The thickness of the film build measured from the vehicle body and quality measurement system (QMS) quality characteristics (gloss, distinctiveness of image, orange peel, and their aggregated value) are the outputs of the paint process. However, the film thickness and the QMS quality characteristics of the paint may vary with location due to geometric differences of the vehicle body. These output characteristics also vary from vehicle body to vehicle body because of process variability.
Although most of the process parameters (bell speed, paint flows, humidity, booth air flows) are controlled by feedback control systems, the paint process as a system is not automatically controlled. As a result, it is desirable to provide an automatic integrated paint quality control system that monitors and supervisory controls the paint process in terms of paint quality characteristics—film thickness and QMS. It is also desirable to provide an integrated paint quality control system that minimizes the number of vehicles that lack paint thickness uniformity in painting of vehicle bodies. It is further desirable to provide an integrated paint quality control system that allows for quick identification of paint variability and immediately responds with proper adjustment of settings for a paint booth for painting vehicle bodies.